The present invention is in the field of covers for large valves in pipelines for petroleum, steam works, and elsewhere.
Presently, the most popular type of pipe insulation for indoor use is an asbestos mixture. In outdoor application, of course, weatherproof insulation and coverings must be used on pipes where freezing, heat loss, or other heat transfers might be a problem. A number of different techniques and devices have been developed for covering straight pipe, curved elbows, and other irregularities in the pipeline, and valve housings as well, as is illustrated by U.S. Pat. Nos. 3,495,629, 3,559,694, which show elbow covers, and Pat. Nos. 3,556,158, and 3,724,491, which disclose valve covers. However, there has not been developed a valve cover which combines the advantageous aspects of complete flexibility, lightness in weight, toughness made possible by modern synthetic fabrics, and a waterproof exterior, and the entire cover being simply removable from the valve and reinstallable to permit easy access for maintenance.